However, I can't think of anything that has involved Jim Henson's creations and ideas, without having Jim Henson's actually involvement, that has worked for me. His death left a huge void in his creations, in my opinion.

I loved the film as a kid, but it's not one of those movies that hold much nostalgia, let alone adult enjoyment, for me. I think I've watched it once in the last twenty years. Whether I have any interest in seeing a sequel will depend on how good the previews look, I guess.